There is the leaf shutter vs focal plane shutter and mirror bounce arguments that have to go into this against the TLR, but then the RF camera is hard on macro photography and parallax in general causing offsets in the image. All of the above posts are true as well. It is what you prefer.
The Mamiya RZ has the best of both worlds as much as is possible. The low mirror bounce and a leaf shutter. The weight makes camera movement from the mirror very low.